Methods and apparatus for payload estimation and hitch condition detection using integrated sensors

ABSTRACT

Methods, apparatus, systems and articles of manufacture are disclosed for payload estimation and fault detection using hitch integrated sensors. An example apparatus includes a pin orientation determiner to determine a first orientation of a first pin and a second orientation of a second pin, the first pin and the second pin disposed within a hitch and calculate a relative orientation of the first pin and the second pin based on the first orientation and the second orientation. The example apparatus further includes a hitch condition detector to determine if a physical change has occurred in the hitch by comparing the relative orientation to an installation orientation of the first pin and the second pin.

FIELD OF THE DISCLOSURE

This disclosure relates generally to vehicle hitches and, moreparticularly, to methods and apparatus for payload estimation and faultdetection using hitch integrated sensors.

BACKGROUND

In recent years, consumer vehicles have increasingly been used fortowing or hauling cargo. Consumer vehicles often have limits associatedwith the payloads capable of being hauled and towed by the vehicles.Operating outside of these limits can cause unnecessary wear and/ordamage to the vehicle. Consumer vehicles capable of pulling trailershave implemented additional data processing capabilities.

SUMMARY OF INVENTION

An example apparatus disclosed herein includes a pin orientationdeterminer to determine a first orientation of a first pin and a secondorientation of a second pin, the first pin and the second pin disposedwithin a hitch, and calculate a relative orientation of the first pinand the second pin based on the first orientation and the secondorientation, and a hitch condition detector to determine if a physicalchange has occurred in the hitch by comparing the relative orientationto an installation orientation of the first pin and the second pin.

An example method disclosed herein includes determining a firstorientation of a first pin and a second orientation of a second pin, thefirst pin and the second pin disposed within a hitch, calculating arelative orientation of the first pin and the second pin based on thefirst orientation and the second orientation, and determining if aphysical change has occurred in the hitch by comparing the relativeorientation to an installation orientation of the first pin and thesecond pin.

An example non-transitory machine-readable storage medium disclosedherein includes instructions which, when executed, cause a processor toat least determine a first orientation of a first pin and a secondorientation of a second pin, the first pin and the second pin disposedwithin a hitch, calculate a relative orientation of the first pin andthe second pin based on the first orientation and the secondorientation, and determine if a physical change has occurred in thehitch by comparing the relative orientation to an installationorientation of the first pin and the second pin.

An example apparatus disclosed herein includes a hitch change detectorto detect, via an accelerometer of a hitch, a pitch angle change of avehicle, and a payload determiner to determine if a hitch load changeoccurred within a threshold time after the pitch angle change, and inresponse to determining the hitch load change occurred within thethreshold time, calculate a weight associated with a payload within abed of the vehicle based on a property of the vehicle.

An example method disclosed herein includes detecting, via anaccelerometer of a hitch, a pitch angle change of a vehicle, determiningif a hitch load change occurred within a threshold time after the pitchangle change, and in response to determining the hitch load changeoccurred within the threshold time, calculating a weight associated witha payload within a bed of the vehicle based on a property of thevehicle.

An example non-transitory machine-readable storage medium disclosedherein includes instructions which, when executed, cause a processor toat least detect, via an accelerometer of a hitch, a pitch angle changeof a vehicle, determine if a hitch load change occurred within athreshold time after the pitch angle change, and in response todetermining the hitch load change occurred within the threshold time,calculate a weight associated with a payload within a bed of the vehiclebased on a property of the vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example system including a vehicle hauling apayload and towing a trailer in which the examples disclosed herein maybe implemented.

FIG. 2 illustrates an example hitch including sensor pins with which theexamples disclosed herein may be implemented.

FIG. 3 illustrates example interior views of the sensor pins of FIG. 2.

FIG. 4 is a block diagram detailing the load manager of FIG. 1.

FIG. 5A illustrates an example loading condition of a vehicle with apayload or a trailer.

FIG. 5B illustrates an example loading condition of a vehicle caused bya payload disposed in the bed of the vehicle.

FIGS. 6A-6C illustrate example configurations of the sensor pins of FIG.2.

FIGS. 7-9 are flowcharts representative of machine readable instructionsthat may be executed to implement the load manager of FIGS. 1 and/or 3.

FIG. 10 is a block diagram of an example processing platform structuredto execute the instructions of FIGS. 7-9 to implement the load managerof FIGS. 1 and/or 3.

The figures are not to scale. In general, the same reference numberswill be used throughout the drawing(s) and accompanying writtendescription to refer to the same or like parts.

Descriptors “first,” “second,” “third,” etc. are used herein whenidentifying multiple elements or components which may be referred toseparately. Unless otherwise specified or understood based on theircontext of use, such descriptors are not intended to impute any meaningof priority, physical order or arrangement in a list, or ordering intime but are merely used as labels for referring to multiple elements orcomponents separately for ease of understanding the disclosed examples.In some examples, the descriptor “first” may be used to refer to anelement in the detailed description, while the same element may bereferred to in a claim with a different descriptor such as “second” or“third.” In such instances, it should be understood that suchdescriptors are used merely for ease of referencing multiple elements orcomponents.

DETAILED DESCRIPTION

Vehicles (e.g., trucks, etc.) often include external hitches coupled therear of the vehicle. In some examples disclosed herein, the hitchincludes one or more pins having magneto-elastic sensors to determinethe force being applied via a trailer coupled to a receiver tube of thehitch. The pin(s) of the hitch can be used to determine a tongue weightand a towed weight of an attached trailer. An example of a hitch systemwith sensor pins is described in U.S. application Ser. No. 16/230,776,which is hereby incorporated herein by reference in its entirety.

In some examples, magneto-elastic pins use flux gates to measure a towedweight or load (e.g., the shear force) applied to the pins. In suchexamples, the flux gates are orientated such that they measure the loadin the direction the load is applied. Accordingly, rotation of thepin(s) within the hitch can cause the magneto-elastic sensor(s) torecord an incorrect tongue and/or towed weight. Accordingly, in someexamples, the sensor pins include accelerometers to measure theorientations of the pins. However, because accelerometers measure therotational orientations of the pins relative to gravity, a change in ameasurement of the accelerometers cannot be differentiated between thevehicle operating on a grade and the rotation of the pins within thehitch.

In some examples, when a trailer is coupled to a hitch of a vehicle or apayload is disposed within a bed of the vehicle, the vehicle squats. Asused herein, the terms “squat” and “squats” refer to the deflection of arear portion of a vehicle (e.g., a downward deflection of a rear portionof a vehicle, an upward deflection of a front portion of a vehicle,etc.) caused by towing a trailer and/or hauling a payload. In someexamples, vehicle squat can be caused by the compression and/ordeflection of one or more suspension elements associated with the rearaxle of a vehicle.

Examples disclosed herein address the above-noted problems using a hitchthat includes two sensor pins with incorporated accelerometers. In someexamples disclosed herein, a first pin includes a first accelerometerand a second sensor pin including a second accelerometer. In someexamples disclosed herein, the first accelerometer and the secondaccelerometer are installed at an installation orientation. In someexamples, the current relative orientation of pins can be determined bycomparing the data from the accelerometers with respect to gravity. Insuch examples, if the current relative orientation is not the same asthe installed orientation, a physical change can be inferred to haveoccurred in the hitch and/or vehicle. In some examples disclosed herein,the current relative orientation of the pins can be further compared toa vehicle orientation determined by an on-board accelerometer associatedwith the vehicle. In some examples herein, acceleration values from thefirst accelerometer and/or the second accelerometer can be used todetermine a squat of the vehicle. In some examples disclosed herein, thepayload disposed in the vehicle can be determined using the squat of thevehicle, a suspension property and/or a vehicle configuration.

FIG. 1 illustrates an example system 100 including an example vehicle102 hauling an example payload 104 and towing an example trailer 106 inwhich the examples disclosed herein may be implemented. In theillustrated example of FIG. 1, the trailer 106 is coupled to the vehicle102 via an example hitch 108. The system 100 further includes an exampleRCM 110 and an example load manager 112. While the RCM 110 and the loadmanager 112 are depicted as part of the hitch 108 and vehicle 102,respectively, the RCM 110 and load manager 112 can be implemented by anysuitable component of the vehicle 102, the trailer 106, and/or the hitch108. Additionally or alternatively, the RCM 110 and/or load manager 112can be implemented by a computing device (e.g., a mobile phone, etc.)associated with a user of the vehicle 102.

In the illustrated example of FIG. 1, the trailer 106 is coupled to thevehicle 102 via a receiver tube of the hitch 108. In some examples, thetrailer 106 is pivotally coupled to the hitch 108 via a tow ball. In theillustrated example, the vehicle 102 includes an open-air bed 114disposed over a rear axle 116 of the vehicle 102. In other examples, thevehicle 102 can include an enclosed bed, a trunk and/or a cargo areabehind the rear seats. In the illustrated example, the vehicle 102 is apickup truck. In other examples, the vehicle 102 can be any othersuitable type of vehicle (e.g., a commercial truck, a motorcycle, amotorized cart, an all-terrain vehicle, etc.)

In the illustrated example, the payload 104 is an item(s) loaded in thebed 114 of the vehicle 102. In the illustrated example, the payload 104causes the vehicle 102 to squat by compressing and/or deflecting asuspension element of the rear axle 116 of the vehicle 102. In someexamples, the payload 104 can be loaded in any other location that wouldcause the vehicle 102 to squat. For example, the payload 104 can beloaded in the trunk and/or rear seat of the vehicle 102.

The trailer 106 is a towed container coupled to the vehicle 102 via thehitch 108. In the illustrated example, the trailer 106 exerts a verticalload (e.g., a tongue load, etc.) on the vehicle 102. In some examples,the tongue load can cause the vehicle 102 to squat. In some examples,while the vehicle 102 is moving, the trailer 106 exerts a towed load onthe vehicle 102. In some examples, the hitch 108 includes a first sensorpin and a second sensor pin. In some examples, the hitch 108, via thefirst sensor pin and/or the second sensor pin, can detect and measurethe tongue load and/or towed load exerted by the trailer 106. In someexamples, the hitch 108, via the first sensor pin and/or the secondsensor pin, can detect and measure the pitch of the hitch 108. Theexample hitch 108 is described in greater detail in conjunction withFIG. 2.

The example RCM 110 is a system included in the vehicle 102 thatcontrols safety features of the vehicle 102. In some examples, the RCM110 includes sensors (e.g., accelerometers, etc.) and can receive inputsthat cause the safety features to activate. In some examples, the RCM110 is implemented as an electronic control unit (ECU) and cancommunicate with a main computer of the vehicle 102 and/or the loadmanager 112.

The load manager 112 receives load and/or pitch information from thehitch 108 and the RCM 110. For example, the load manager 112 can analyzethe load information to determine the towed load, tongue load or and/orthe load associated with the payload 104. In some examples, the loadmanager 112 can analyze the received load information to determine thesquat of the vehicle 102. Further, the load manager 112 can determinethe squat of the vehicle 102 based on pitch data (e.g., accelerationvalues, etc.) received from the hitch 108. In some examples, the loadmanager 112 can detect a load and/or pitch change associated with thecoupling of the trailer 106 to the vehicle 102 and can analyze thereceived load/or pitch information to determine if a physical change inthe hitch 108 and/or the vehicle 102 has occurred. For example, aphysical change in the hitch 108 and/or the vehicle 102 can include amechanical fault in the hitch 108 and/or any other change that causes anincorrect load to be measured by the load manager 112. Examplemechanical faults include deformation of pin rotation preventionfeatures of the hitch 108 (e.g., the rounding of a D-shaped restrainingplate, etc.), the mechanical yielding of one or more parts of the hitch108, the loosening of one or more fasteners associated with the hitch108, etc. The example load manager 112 is described in greater detail inconjunction with FIG. 4.

FIG. 2 illustrates the example hitch 108 of FIG. 1 in further detail.The example hitch 108 includes an example housing 202, an examplecrossbar 204, an example first sensor pin 206, an example second sensorpin 208 and an example receiver tube 210. While the illustrated exampleof FIG. 2 illustrates one potential configuration of the hitch 108, thehitch 108 can have any other suitable structure and/or design.

The housing 202 houses the first sensor pin 206 and the second sensorpin 208. In the illustrated example, the housing 202 is coupled to thereceiver tube 210 via a weld, a press fit, one or more fasteners and/orany other similar means. In the illustrated example of FIG. 2, thehousing 202 is a single continuous part. In other examples, the housing202 can be composed any number discrete pieces (e.g., 2 parts, etc.).Additionally, the housing 202 is coupled to the crossbar 204 viafasteners (e.g., bolts, screws, etc.). In other examples, any othersuitable means of coupling the housing 202 to the crossbar 204 can beused (e.g., a weld, a press fit, etc.). In some examples, the housing202 is shaped to prevent the first sensor pin 206 and/or the secondsensor pin 208 from rotating. For example, the housing 202 can have aD-shaped adapter at the one or both ends of apertures 212, 214 receivingthe first sensor pin 206 and/or the second sensor pin 208. In someexamples, one or both of the apertures 212, 214 can include any othersuitable restraining features to prevent the sensor pins 206, 208 fromrotating within the housing 202. Additionally or alternatively, thehousing 202 can include any other suitable features (e.g., teeth, etc.)to prevent the sensor pins 206, 208 from rotating within the housing202. The example housing 202 can be composed of metal or any combinationof metals (e.g., steel, aluminum, etc.), composites (e.g., carbon fiber,etc.), plastics and/or any other suitable materials.

The crossbar 204 is a structural element that connects the housing 202to the vehicle 102. In the illustrated example, the crossbar 204 has afilleted square cross-section. In other examples, the crossbar 204 canhave any other suitable cross-section (e.g., quadrilateral, polygonal,circular, ovoid, etc.). In the illustrated example, the crossbar 204 isa single continuous tube disposed in the housing 202. In other examples,the crossbar 204 can be composed of two or more structural elements. Theexample crossbar 204 can be composed of metal or any combination ofmetals (e.g., steel, aluminum, etc.), composites (e.g., carbon fiber,etc.), plastics and/or any other suitable materials.

The first sensor pin 206 and the second sensor pin 208 are disposed withthe example housing 202 and include force sensing elements (e.g.,magnetoelastic sensors, strain gages, load cells, hydraulic load cells,etc.) and accelerometers. In some examples, when consideredindividually, the sensor pins 206, 208 are capable of measuring forcesin two directions. In the illustrated example, when used together, thesensor pins 206, 208 can measure the forces in three directions,including the tongue load (e.g., a load applied in a directionorthogonal to the ground, etc.), the towed load (e.g., a load applied ina direction parallel to the receiver tube 210, etc.), and thelongitudinal load (e.g., a load applied in a direction parallel to thecrossbar 204, etc.). In the illustrated example, the sensor pins 206,208, via the incorporated accelerometers, can detect an orientation ofthe hitch 108 and/or the sensor pins 206, 208, etc. In the illustratedexample, the first sensor pin 206 and the second sensor pin 208 areconfigured within the hitch 108 such that the first sensor pin 206 andthe second sensor pin 208 form part of the only load path between thetrailer 106 and the vehicle 102. In the illustrated example, the firstsensor pin 206, the second sensor pin 208 and the housing 202 areconfigured such that the relative orientation of the sensor pins 206,208 remains constant unless a physical change occurs (e.g., the housing202 is rigid, etc.).

In the illustrated example of FIG. 2, the sensor pins 206, 208 havesubstantially the same lengths, cross-sections, load ratings anddiameters. In other examples, the sensor pins 206, 208 can havedifferent lengths, cross-sections, load ratings, and/or diameters. Insome examples, the first sensor pin 206 and/or the second sensor pin 208can have a have a hollow cross-section. In some examples, the firstsensor pin 206 and the second sensor pin 208 are composed of a ferrousmaterial (e.g., high strength steel, etc.). In other examples, thesensor pin 206 and the second sensor pin 208 can be any other suitablematerial. In some examples, the sensor pins 206, 208 are atsubstantially the same vertical position relative to the crossbar 204.

The receiver tube 210 enables the trailer 106 to be coupled to thevehicle 102. For example, a tow ball can be coupled to the hitch 108 viathe receiver tube 210. The coupled tow ball enables the trailer 106 tobe pivotally coupled to the vehicle 102 via the hitch 108. In otherexamples, any other suitable coupling element (e.g., a tow bar, etc.)can be coupled to the hitch 108 via the receiver tube 210. In someexamples, the hitch 108 can be further coupled to the trailer 106 viaone or more chains.

FIG. 3 illustrates example interior views 300 of the sensor pins 206,208 of FIG. 2. In the illustrated example of FIG. 3, the example sensorspins 206, 208 are illustrated as transparent with dashed linesindicating the physical boundaries of the sensors pins 206, 208 suchthat the internal components of the sensor pins 206, 208 are visiblewithin. In the illustrated example of FIG. 3, the sensor pins 206, 208are depicted as continuous solid structures. In some examples, one orboth of the sensor pins 206, 208 can be any other suitable shape (e.g.,hollow, tubular, including insert holes, etc.). In some examples, one orboth of the sensors pins 206, 208 can be assemblies of multiple parts.

In the illustrated example of FIG. 3, an example coordinate system 301includes an example x-axis 302, an example y-axis 304 and an examplez-axis 306. In the illustrated example of FIG. 3, the x-axis 302corresponds to a horizontal direction (e.g., a direction to parallel tothe receiver tube 210, etc.). The example y-axis 304 corresponds to alateral direction (e.g., a direction parallel to the crossbar 204,etc.). The example z-axis to a vertical direction (e.g., a directionorthogonal to the ground, etc.). The example first sensor pin 206includes an example first circuit board 308 and an example firstaccelerometer 310 that has an example first accelerometer orientation312. The example second sensor pin 208 includes an example secondcircuit board 314 and an example second accelerometer 316 that has anexample second accelerometer orientation 318.

The circuit boards 308, 314 are printed circuit boards that include thesensors of the sensors pins 206, 208, respectively. In the illustratedexample of FIG. 3, the example circuit boards 308, 314 include theaccelerometers 310, 316 and can further include any other suitablesensors and/or electronics. For example, the circuit boards 308, 314 caninclude force sensors, load sensors, additional accelerometers, fluxgates, temperature sensors, integrated circuit (IC) chips, etc. In someexamples, the circuit boards 308, 314 include a carrier piece tofacilitate the coupling of the circuit boards 308, 314 within thesensors pins 206, 208. In some examples, some or all of the example loadmanager 112 can be implemented via the first circuit board 308 and/orthe second circuit board 314. In some examples, the circuit boards 308,314 can be inserted into axial holes of the sensor pins 206, 208. Insome examples, the sensor pins 206, 208 can be assembled around thecircuit boards 308, 314.

In the illustrated example of FIG. 3, the accelerometers 310, 316 aresingle-axis electromechanical accelerometers. The first accelerometer310 measures the acceleration experienced by the first sensor pin 206 inthe first accelerometer orientation 312. In the illustrated example ofFIG. 3, the first accelerometer orientation 312 is oriented along thez-axis 306. In such examples, the first accelerometer 310 measures theacceleration experienced by the first sensor pin 206 in the z-direction(e.g., the acceleration due to gravity). The example secondaccelerometer 316 measures the acceleration experienced by the secondsensor pin 208 in the second accelerometer orientation 318. In theillustrated example of FIG. 3, the second accelerometer orientation 318is oriented along the x-axis 302. In such examples, the secondaccelerometer 316 measures the acceleration experienced by the firstsensor pin 206 in the x-direction (e.g., the acceleration of the vehicle102). In some examples, the example accelerometers 310, 316 can bemulti-axis accelerometers. In some examples, the example accelerometers310, 316 are piezoelectric accelerometers. In other examples, theexample accelerometers 310, 316 can be any other suitable type ofaccelerometers.

In some examples, the accelerometer orientations 312, 318 correspond tothe orientation of the sensor pins 206, 208. In some examples, if thesensor pins 206, 208 rotate within the hitch 108, the accelerometersorientations 312, 318 rotate a proportional amount. In some examples, achange in the first accelerometer orientation 312 can be associated witha change in the orientation (e.g., rotational position, etc.) of thefirst sensor pin 206. In some examples, a change in the secondaccelerometer orientation 318 is associated with a change in theorientation (e.g., rotational position, etc.) of the second sensor pin208.

In the illustrated example of FIG. 3, the interior views 300 correspondto the condition (e.g., the installation orientation, etc.) of thesensor pins 206, 208 as the sensors pins 206, 208 were installed in thehitch 108. An example installation orientation of the sensor pins 206,208 is discussed in further detail below in conjunction with FIG. 6A. Insome examples, the directions of the accelerometer orientations 312, 318can change relative to the coordinate system 301 based on a grade of adriving surface on which the vehicle 102 is located, the addition of thepayload 104 to the vehicle 102, the coupling of the trailer 106 to thehitch 108, the occurrence of a physical change in the hitch 108 and/orthe vehicle 102, etc. An example orientation of the sensor pins 206, 208while the vehicle 102 is on grade and/or the vehicle is loaded with aload is discussed in greater detail below in conjunction with FIG. 6B.

In some examples, the directions of the example accelerometerorientations 312, 318 can change relative to each other based on theoccurrence of a physical change in the hitch 108 and/or vehicle 102. Forexample, in the illustrated example of FIG. 3, the accelerometerorientations 312, 318 are oriented at 90 degrees relative to one another(e.g., example first accelerometer orientation 312 is oriented in thenegative z-direction and the example second accelerometer orientation318 is oriented in the positive x-direction, etc.). In such examples, ifa physical change in the hitch 108 and/or vehicle 102 has occurred, theaccelerometer orientations 312, 318 can be oriented at a non-orthogonalorientation relative to one another. An example orientation of thesensor pins 206, 208 after a physical change in the hitch 108 and/orvehicle 102 has occurred is discussed in greater detail below inconjunction with FIG. 6C.

FIG. 4 is an example block diagram detailing the load manager 112 ofFIG. 1. The load manager 112 includes an example sensor interface 402,an example change detector 404, an example payload determiner 406, anexample pin orientation determiner 408, an example hitch conditiondetector 410, and an example vehicle interface 412.

The sensor interface 402 receives data from sensors associated with thehitch 108 and/or the RCM 110. For example, the sensor interface 402 canreceive input from the sensor pins 206, 208, an accelerometer associatedwith the RCM 110 and/or any other sensors associated with the hitch 108and/or vehicle 102. In some examples, the sensor interface 402 canfacilitate communication between the change detector 404, the examplepayload determiner 406, the pin orientation determiner 408, the hitchcondition detector 410 and/or the vehicle interface 412. In someexamples, the sensor interface 402 can convert the received signal fromthe sensor(s) into a numerical form (e.g., human readable, etc.). Forexample, if the sensor pins 206, 208 output analog signals (e.g., ananalog voltage, an analog current, etc.) the sensor interface 402 canconvert the received signals into data values corresponding to a towedload, a tongue load, a longitudinal load and/or orientation (e.g., thepitch, etc.) of the sensor pins 206, 208.

The example change detector 404 analyzes the received sensor data todetermine if a towed load and/or tongue load has been applied to thevehicle 102 (e.g., caused by the coupling of the trailer 106, etc.) Forexample, the change detector 404 can detect changes in the signalassociated with the towed load and/or tongue load. In some examples, thechange detector 404 can determine when a change in the tongue loadand/or the towed load occurred. In some examples, the change detector404 can determine a time at which when a pitch change of the sensor pins206, 208 occurred. In some examples, the change detector 404 can storethe determined time in a memory associated with the load manager 112.

The example payload determiner 406 determines if a payload (e.g., thepayload 104 of FIG. 1) has been added to the vehicle 102. In someexamples, the payload determiner 406 can determine the load associatedwith the payload 104. For example, the payload determiner 406 candetermine if a pitch change of the hitch 108 occurred at the same timeas a change in tongue load and/or towed load. In examples where a pitchchange occurred within a threshold time period of change in the tongueload and/or towed load, the payload determiner 406 can determine thepitch change is associated with the coupling of a trailer to the vehicle102. In examples where the pitch change occurred outside of thethreshold time period or no hitch load was detected, the payloaddeterminer 406 can determine the payload 104 has been added to thevehicle 102. In some examples, the payload determiner 406 can calculatethe load associated with the payload 104 based on the pitch changeassociated with the sensor pins 206, 208, a configuration of the vehicle102 and/or a suspension property (e.g., a stiffness of an elasticelement of the suspension, etc.) of the vehicle 102. For example, thepayload determiner 406 can determine the load based on an empiricallyderived squat to payload relationship. For example, the payloaddeterminer 406 can calculate the payload based on the payload beingproportional to the squat of the vehicle 102, and a suspension-squatconstant. In some examples, the suspension-squat constant is the loadassociated with one degree of squat change. In other examples, thesuspension-squat constant can be any suitable value or calculated by anysuitable equation. In some examples, the payload determiner 406 candetermine the load associated with the payload by any other suitablemethod (e.g., a lookup table, etc.). In some examples, the payloaddeterminer 406 does not use sensors associated with the suspensionsystem of the vehicle 102 (e.g., a ride height sensor, an elasticelement sensor, etc.).

The example pin orientation determiner 408 determines the relativeorientation of the sensor pins 206, 208 by comparing the pitch datareceived from the accelerometers of the sensor pins 206, 208. Forexample, the pin orientation determiner 408 can determine theorientation of the first sensor pin 206 using pitch data from the firstsensor pin 206 and the acceleration associated with gravity, (e.g., g,etc.). For example, the pin orientation determiner 408 can determine theorientation of the second sensor pin 208 using the pitch data from thefirst sensor pin 206 and the acceleration associated with gravity. Insome examples, the pin orientation determiner 408 can determine therelative orientation of the sensor pins 206, 208 using the orientationof the first sensor pin 206 (e.g., the orientation of an accelerometerwithin the first sensor pin 206, etc.) and the orientation of the secondsensor pin 208 (e.g., the orientation of an accelerometer within thesecond sensor pin 208, etc.).

In some examples, the pin orientation determiner 408 can compare therelative orientation of the pins with the installation orientation ofthe sensor pins 206, 208. In such examples, the pin orientationdeterminer 408 can retrieve the installation orientation of the sensorpins 206, 208 from a memory associated with the hitch 108, the vehicle102, the load manager 112, etc. In some examples, the installationorientation of the sensor pins 206, 208 is 90 degrees. In some examples,pin orientation determiner 408 can determine the difference between theinstalled orientation and the relative orientation. For example, the pinorientation determiner 408 can determine the difference by subtractingthe relative orientation of the sensor pins 206, 208 from theinstallation orientation of the sensor pins 206, 208. In other examples,the pin orientation determiner 408 can determine the difference betweenthe installation orientation of the sensor pins 206, 208 and therelative orientation of the sensor pins 206, 208 using any othersuitable equation and/or method.

The example hitch condition detector 410 determines if a physical changein the vehicle 102 and/or hitch 108 has occurred. For example, the hitchcondition detector 410 can analyze the difference between theinstallation orientation and relative orientation. In some examples, ifthe difference between the installation orientation and relativeorientation satisfies a threshold (e.g., substantially equal to zerodegrees, etc.), the hitch condition detector 410 can determine no faulthas occurred. In other examples, if the difference between theinstallation orientation and relative orientation does not satisfy thethreshold, the hitch condition detector 410 can determine a physicalchange in the vehicle 102 and/or hitch 108 has occurred.

The vehicle interface 412 communicates with a computer associated withthe vehicle 102. For example, if the hitch condition detector 410determines a fault has occurred, the vehicle interface 412 can cause auser interface (e.g., a display, etc.) associated with the vehicle 102to present an alert to a user of the vehicle 102. In some examples, thevehicle interface 412 can further cause a user interface to present thedetermined squat, the determined tongue load, the determined towed load,the determined load associated with the payload 104, etc. In someexamples, the vehicle interface 412 can retrieve or send any othersuitable information associated with the vehicle 102, hitch 108, etc.

While an example manner of implementing the load manager 112 of FIG. 1is illustrated in FIG. 4, one or more of the elements, processes and/ordevices illustrated in FIG. 4 may be combined, divided, re-arranged,omitted, eliminated and/or implemented in any other way. Further, theexample sensor interface 402, the example change detector 404, theexample payload determiner 406, the example pin orientation determiner408, the example hitch condition detector 410 and/or, more generally,the example load manager 112 of FIG. 1 may be implemented by hardware,software, firmware and/or any combination of hardware, software and/orfirmware. Thus, for example, any of the example sensor interface 402,the example change detector 404, the example payload determiner 406, theexample pin orientation determiner 408, the example hitch conditiondetector 410 and/or, more generally, the example load manager 112 couldbe implemented by one or more analog or digital circuit(s), logiccircuits, programmable processor(s), programmable controller(s),graphics processing unit(s) (GPU(s)), digital signal processor(s)(DSP(s)), application specific integrated circuit(s) (ASIC(s)),programmable logic device(s) (PLD(s)) and/or field programmable logicdevice(s) (FPLD(s)). When reading any of the apparatus or system claimsof this patent to cover a purely software and/or firmwareimplementation, at least one of the example, sensor interface 402, theexample change detector 404, the example payload determiner 406, theexample pin orientation determiner 408, and/or the example hitchcondition detector 410 is/are hereby expressly defined to include anon-transitory computer readable storage device or storage disk such asa memory, a digital versatile disk (DVD), a compact disk (CD), a Blu-raydisk, etc. including the software and/or firmware. Further still, theexample load manager 112 of FIG. 1 may include one or more elements,processes and/or devices in addition to, or instead of, thoseillustrated in FIG. 4, and/or may include more than one of any or all ofthe illustrated elements, processes and devices. As used herein, thephrase “in communication,” including variations thereof, encompassesdirect communication and/or indirect communication through one or moreintermediary components, and does not require direct physical (e.g.,wired) communication and/or constant communication, but ratheradditionally includes selective communication at periodic intervals,scheduled intervals, aperiodic intervals, and/or one-time events.

FIG. 5A illustrates an example loading condition 500 of an examplevehicle 502. The vehicle 502 includes an example bed 504 and an examplecenter line 506. In some examples, the vehicle 502 can correspond withthe vehicle 102 of FIG. 1. In the illustrated example of FIG. 5A, thevehicle 502 is not hauling any payload in the bed 504. In theillustrated example, the vehicle 502 is not experiencing any squat(e.g., the rear suspension is not more compressed than the frontsuspension of the vehicle 102, etc.). In the illustrated example, thecenter line 506 is parallel to the driving surface.

FIG. 5B illustrates an example loading condition 508 of the examplevehicle 502 of FIG. 5A caused by an example payload 510 loaded in thebed 504 of the vehicle 502. The example loading condition 508 is causedby the example payload 510 and causes an example deflection 512 from thecenter line 506 and an example squat 514. In the illustrated example,the deflection 512 is caused by the payload 510 compressing one or moresuspension elements of the vehicle 102. In some examples, the loadmanager 112 can determine the weight of the payload 104 based on thesquat 514 and a property of the vehicle 502 (e.g., a stiffness of therear suspension of the vehicle, a configuration of the vehicle 502,etc.). In some examples, the squat 514 can be determined by the pitchdata received from the accelerometers of the first sensor pin 206 and/orthe second sensor pin 208.

FIG. 6A illustrates an example configuration 600 of the sensor pins 206,208 of FIG. 2 corresponding to a vehicle on a flat surface. In theillustrated example of FIG. 6A, an example vehicle orientation 602corresponds to the orientation of a vehicle on a flat surface (e.g., theorientation as determined by the on-board accelerometer of the vehicle102, etc.) and includes an example X-axis 604 (e.g., an axis in theparallel to the driving surface, etc.) and an example Z-axis 606 (e.g.,an axis orthogonal to the driving surface, etc.). The first sensor pin206 includes an example first accelerometer 607 with an example firstaccelerometer orientation 608 aligned with the Z-axis 606 and theexample second sensor pin 208 includes an example second exampleaccelerometer 609 with an example second accelerometer orientation 610aligned with the X-axis 604. In the illustrated example of FIG. 6A, thesensor pins 206, 208 are subjected to an acceleration due to gravity(e.g., g, etc.) which is illustrated as an example gravity vector 614.In some examples, the accelerometers 607, 609 correspond to theaccelerometers 310, 316 of FIG. 3.

In some examples, the accelerometers 607, 609 measure the magnitude ofacceleration experienced by the sensor pins 206, 208 occurring in thedirections of the accelerometer orientations 608, 610. In some examples,when the vehicle 102 is stationary, the sensor pins 206, 208 are onlysubjected to the acceleration due to gravity. Accordingly, therelationship between the acceleration due to gravity and the magnitudeof the acceleration value measured by the first accelerometer 607 can bedetermined via trigonometric relationships. In some examples, theacceleration value measured by the first accelerometer 607 isproportional to the acceleration due to gravity and the angle betweenthe accelerometer orientation 608 and the gravity vector 614 (e.g., θ₁,etc.). Similarly, the relationship between the acceleration due togravity and the magnitude of acceleration value measured by the secondaccelerometer 609 can be determined via trigonometric relationships. Insome examples, the acceleration value measured by the secondaccelerometer 609 is proportional to the acceleration due to gravity andthe angle between the second accelerometer orientation 610 and thegravity vector 614 (e.g., θ₂, etc.). The relationship of theacceleration value measured by the first accelerometer 607 and thegravity vector 614 and the acceleration value measured by the secondaccelerometer 609 and the gravity vector 614 can be used to calculatethe angle between the first accelerometer orientation 608 and thegravity vector 614 and the second accelerometer orientation 610 and thegravity vector 614, respectively:

$\begin{matrix}{\theta_{1} = {\cos^{- 1}\left( \frac{a_{first}}{g} \right)}} & (1) \\{\theta_{2} = {\cos^{- 1}\left( \frac{a_{second}}{g} \right)}} & (2)\end{matrix}$

where θ₁ is the angle between the first accelerometer orientation 608and the gravity vector 614, θ₂ is the angle between the secondaccelerometer orientation 610 and the gravity vector 614, a_(first) isthe acceleration value measured by the first accelerometer 607,a_(second) is the acceleration value measured by the secondaccelerometer 609, and g is the acceleration due to gravity. In someexamples, the relative orientation of the sensor pins 206, 208 (e.g.,the current orientation of the pins, etc.) can be determined based onthe difference between θ₁ and θ₂. In some examples, the relativeorientation of the sensor pins 206, 208 can be compared to theinstallation orientation of the sensor pins 206, 208 to determine if aphysical change in the hitch 108 and/or vehicle 102 has occurred.

Additionally or alternatively, the acceleration value measured by thefirst accelerometer 607 or the second accelerometer 609 can be used toverify the acceleration value measured by the other accelerometer. Forexample, if the accelerometers 607, 609 are installed orthogonally(e.g., the angular difference between the first accelerometerorientation 608 and the second accelerometer orientation 610 is equal to90 degrees, etc.), the acceleration value measured by the firstaccelerometer 607 can be used to verify the acceleration value of thesecond accelerometer 609 using Equation (3):

a _(second,estimated) =g sin θ₁  (3)

where a_(second,estimated) is the estimated acceleration valuedetermined using θ₁. Similarly, if the accelerometers 607, 609 areinstalled orthogonally (e.g., Δθ_(intall) is equal to 90 degrees, etc.),the acceleration value measured by the second accelerometer 609 can beused to verify the acceleration value measured by the secondaccelerometer 609 using Equation (4):

a _(first,estimated) =g sin θ₂  (4)

Accordingly, the estimated acceleration values (e.g.,a_(first,estimated), a_(second,estimated), etc.) determined viaEquations (3) and/or (4) can be compared to the values measured via theaccelerometer 608 and/or the second accelerometer 610. In such examples,the difference between the estimated acceleration value and the measuredacceleration value can be compared to a threshold to determine if thesensor pins 206, 208 have been displaced from the installationorientation. In some examples, if the pins 206, 208 are not installed ata non-orthogonal orientation, other equations can be used to verify theacceleration values of the pins 206, 208.

Returning to the configuration 600 of FIG. 6A, the sensor pins 206, 208have not rotated from the installation orientation (e.g., theaccelerometers orientations 608, 610 are orthogonally oriented, etc.).In the illustrated example of FIG. 6A, the first accelerometer 607measures an acceleration value of g and the pin orientation determiner408 can solve Equation (1) to determine that θ₁ is 0 degrees. In theillustrated example of FIG. 6A, the accelerometer 609 measures anacceleration value of 0 and the pin orientation determiner 408 can solveEquation (2) to determine that θ₂ is 90 degrees. In some examples, thepin orientation determiner 408 can compare θ₁ and θ₂ (e.g., determinethe difference, etc.) to determine that the current relative orientationof the pins is 90 degrees. Accordingly, the pin orientation determiner408 can compare the current relative orientation of the sensor pins 206,208 to the installed orientation of the sensor pins 206, 208. In theillustrated example of FIG. 6A, because the sensor pins 206, 208 havenot been displaced from the installation orientation, the hitchcondition detector 410 determines that no fault has occurred.

FIG. 6B illustrates an example configuration 616 of the sensor pins 206,208 of FIG. 2 corresponding to a vehicle on a sloped surface and/orexperiencing a squat. In the illustrated example of FIG. 6B, the vehicleorientation 618 includes an example X′-axis 620, an example Z′-axis 622and the example X-axis 604. The example configuration 616 includes theexample first sensor pin 206 with the example first accelerometer 607 inthe example first accelerometer orientation 608 aligned with the Z′-axis622. The example configuration 616 further includes the example secondsensor pin 208 with the second accelerometer 609 in the example secondaccelerometer orientation 610 aligned with the X′-axis 620. In theillustrated example of FIG. 6B, the sensor pins 206, 208 are subjectedto an acceleration due to gravity (e.g., g, etc.), which is illustratedas an example gravity vector 614.

In some examples, the vehicle orientation 618 can correspond to theorientation of a vehicle on a sloped surface (e.g., the orientation asdetermined by the accelerometer of the vehicle 102, etc.). In otherexamples, the vehicle orientation 618 can correspond to the orientationof a vehicle experiencing a squat (e.g., the vehicle 502 of FIG. 5B,etc.). In such examples, the example X-axis 604 corresponds to theexample center line 506 of FIGS. 4A and 4B, the example X′-axis 620corresponds to the example deflection line of 512 and the angle betweenX′-axis 620 and the X-axis 604 (e.g., θ_(squat), etc.) is the examplesquat 514. In such examples, the example squat 514 can be determinedbased on the angle between the first accelerometer orientation 608 andthe gravity vector 614.

In the illustrated example of FIG. 6B, the sensor pins 206, 208 have notrotated from the installation orientation (e.g., the sensor pins 206,208 are orthogonally oriented, etc.) but the angles between theaccelerometer orientations 608, 610 and the gravity vector 614 (e.g.,θ₁, θ₂, etc.) have changed when compared to the configuration of FIG.6A. In the illustrated example of FIG. 6B, the first accelerometer 607measures a non-zero first acceleration value and the pin orientationdeterminer 408 solves Equation (1) to determine θ₁. In the illustratedexample of FIG. 6B, the accelerometer 610 measures a second non-zeroacceleration value and the pin orientation determiner 408 solvesEquation (2) to determine θ₂. In some examples, the pin orientationdeterminer 408 can compare the difference between θ₁ and θ₂ to determinethat the current relative orientation of the pins is 90 degrees.Accordingly, the pin orientation determiner 408 can compare the currentrelative orientation of the sensor pins 206, 208 to the installedorientation of the sensor pins 206, 208. In the illustrated example ofFIG. 6B, because the sensor pins 206, 208 have not been displaced fromthe installation orientation, the hitch condition detector 410determines that no fault has occurred.

FIG. 6C illustrates an example configuration 626 of the sensor pins 206,208 of FIG. 2 corresponding to a vehicle in which a physical change inthe hitch 108 has occurred. In the illustrated example of FIG. 6C, thevehicle orientation 602 includes the example X-axis 604 and the exampleZ-axis 606. In the illustrated example of FIG. 6C, the sensor pins 206,208 have rotated from the installation orientation (e.g., a physicalchange has occurred in the hitch 108 and/or vehicle 102, etc.). In theillustrated example of FIG. 6B, the first accelerometer 607 measures anon-zero first acceleration value and the pin orientation determiner 408solves Equation (1) to determine θ₁. In the illustrated example of FIG.6C, the second accelerometer 609 measures a second non-zero accelerationvalue and the pin orientation determiner 408 solves Equation (2) todetermine θ₂. In some examples, the pin orientation determiner 408 cancompare θ₁ and θ₂ to determine the current relative orientation of thesensor pins 206, 208. The pin orientation determiner 408 solves comparethe current relative orientation of the sensor pins 206, 208 to theinstalled orientation of the sensor pins 206, 208. In the illustratedexample of FIG. 6C, because the sensor pins 206, 208 have been displacedfrom the installation orientation, the condition detector 410 determinesthat a physical change in the hitch 108 has occurred.

Flowcharts representative of example methods, hardware implemented statemachines, and/or any combination thereof for implementing the loadmanager 112 of FIGS. 1 and/or 3 are shown in FIGS. 7-9. The methods maybe one or more executable programs or portion(s) of an executableprogram for execution by a computer processor such as the processor 1012shown in the example processor platform 1000 discussed below inconnection with FIG. 10. The program may be embodied in software storedon a non-transitory computer readable storage medium such as a CD-ROM, afloppy disk, a hard drive, a DVD, a Blu-ray disk, or a memory associatedwith the processor 1012, but the entire program and/or parts thereofcould alternatively be executed by a device other than the processor1012 and/or embodied in firmware or dedicated hardware. Further,although the example program is described with reference to theflowcharts illustrated in FIG. 7-8, many other methods of implementingthe example load manager 112 may alternatively be used. For example, theorder of execution of the blocks may be changed, and/or some of theblocks described may be changed, eliminated, or combined. Additionallyor alternatively, any or all of the blocks may be implemented by one ormore hardware circuits (e.g., discrete and/or integrated analog and/ordigital circuitry, an FPGA, an ASIC, a comparator, anoperational-amplifier (op-amp), a logic circuit, etc.) structured toperform the corresponding operation without executing software orfirmware.

The machine readable instructions described herein may be stored in oneor more of a compressed format, an encrypted format, a fragmentedformat, a packaged format, etc. Machine readable instructions asdescribed herein may be stored as data (e.g., portions of instructions,code, representations of code, etc.) that may be utilized to create,manufacture, and/or produce machine executable instructions. Forexample, the machine readable instructions may be fragmented and storedon one or more storage devices and/or computing devices (e.g., servers).The machine readable instructions may require one or more ofinstallation, modification, adaptation, updating, combining,supplementing, configuring, decryption, decompression, unpacking,distribution, reassignment, etc. in order to make them directly readableand/or executable by a computing device and/or other machine. Forexample, the machine readable instructions may be stored in multipleparts, which are individually compressed, encrypted, and stored onseparate computing devices, wherein the parts when decrypted,decompressed, and combined form a set of executable instructions thatimplement a program such as that described herein. In another example,the machine readable instructions may be stored in a state in which theymay be read by a computer, but require addition of a library (e.g., adynamic link library (DLL)), a software development kit (SDK), anapplication programming interface (API), etc. in order to execute theinstructions on a particular computing device or other device. Inanother example, the machine readable instructions may need to beconfigured (e.g., settings stored, data input, network addressesrecorded, etc.) before the machine readable instructions and/or thecorresponding program(s) can be executed in whole or in part. Thus, thedisclosed machine readable instructions and/or corresponding program(s)are intended to encompass such machine readable instructions and/orprogram(s) regardless of the particular format or state of the machinereadable instructions and/or program(s) when stored or otherwise at restor in transit.

As mentioned above, the example methods 700, 800, 900 of FIGS. 7-9 maybe implemented using executable instructions (e.g., computer and/ormachine readable instructions) stored on a non-transitory computerand/or machine readable medium such as a hard disk drive, a flashmemory, a read-only memory, a compact disk, a digital versatile disk, acache, a random-access memory and/or any other storage device or storagedisk in which information is stored for any duration (e.g., for extendedtime periods, permanently, for brief instances, for temporarilybuffering, and/or for caching of the information). As used herein, theterm non-transitory computer readable medium is expressly defined toinclude any type of computer readable storage device and/or storage diskand to exclude propagating signals and to exclude transmission media.

“Including” and “comprising” (and all forms and tenses thereof) are usedherein to be open ended terms. Thus, whenever a claim employs any formof “include” or “comprise” (e.g., comprises, includes, comprising,including, having, etc.) as a preamble or within a claim recitation ofany kind, it is to be understood that additional elements, terms, etc.may be present without falling outside the scope of the correspondingclaim or recitation. As used herein, when the phrase “at least” is usedas the transition term in, for example, a preamble of a claim, it isopen-ended in the same manner as the term “comprising” and “including”are open ended. The term “and/or” when used, for example, in a form suchas A, B, and/or C refers to any combination or subset of A, B, C such as(1) A alone, (2) B alone, (3) C alone, (4) A with B, (5) A with C, (6) Bwith C, and (7) A with B and with C. As used herein in the context ofdescribing structures, components, items, objects and/or things, thephrase “at least one of A and B” is intended to refer to implementationsincluding any of (1) at least one A, (2) at least one B, and (3) atleast one A and at least one B. Similarly, as used herein in the contextof describing structures, components, items, objects and/or things, thephrase “at least one of A or B” is intended to refer to implementationsincluding any of (1) at least one A, (2) at least one B, and (3) atleast one A and at least one B. As used herein in the context ofdescribing the performance or execution of processes, instructions,actions, activities and/or steps, the phrase “at least one of A and B”is intended to refer to implementations including any of (1) at leastone A, (2) at least one B, and (3) at least one A and at least one B.Similarly, as used herein in the context of describing the performanceor execution of processes, instructions, actions, activities and/orsteps, the phrase “at least one of A or B” is intended to refer toimplementations including any of (1) at least one A, (2) at least one B,and (3) at least one A and at least one B.

The method 700 of FIG. 7 begins at block 702. At block 702, the sensorinterface 402 receives pin data and/or on-board accelerometer data. Forexample, the sensor interface 402 can receive data from a magnetoelasticforce sensor and/or accelerometers (e.g., the accelerometers 607, 609 ofFIGS. 6A-6C) incorporated in the sensor pins 206, 208. In some examples,the sensor interface 402 can received data from the RCM 110 and/or anyaccelerometer(s) associated with the vehicle 102. In some examples, thesensor interface 402 can receive data from the first sensor pin 206and/or the second sensor pin 208 in an analog format (e.g., a voltage,etc.). In this example, the sensor interface 402 converts the analogformat into a digital value (e.g., a force, a pressure, etc.).

At block 704, the change detector 404 determines if a load change and/orpitch change has been detected. For example, the change detector 404 cananalyze the received pin data to detect a load change and/or pitchchange in the hitch 108. In some examples, the change detector 404determines when the load change and/or the pitch change detected by thesensor pins 206, 208 occurred. If the change detector 404 detects a loadchange and/or pitch change, the method 700 advances to block 706. If thechange detector 404 does not detect a load change and/or pitch change,the method 700 returns to block 702.

At block 706, the payload determiner 406 determines the weight of apayload loaded in the bed 114 of the vehicle 102. The execution of block706 is described in further detail in conjunction with FIG. 8. At block708, the pin orientation determiner 408 determines the relativeorientation of the sensor pins 206, 208 by comparing pin accelerometerdata. The execution of block 708 is described in further detail inconjunction with FIG. 9.

At block 710, the hitch condition detector 410 determines if therelative orientation of pins indicate a physical change in the hitch hasoccurred. For example, the hitch condition detector 410 can determine ifthe difference between the relative orientation of the sensor pins 206,208 and installation orientation of the sensor pins 206, 208 satisfies afirst fault threshold (e.g., zero degrees, five degrees, etc.). If therelative orientation of the pins indicates a physical change in thehitch 108 has occurred (e.g., the first fault threshold is satisfied,etc.), the method 700 advances to block 716. If the relative orientationof the pins does not indicate a physical change in the hitch 108 hasoccurred (e.g., the first fault threshold is not satisfied, etc.), themethod 700 advances to block 712.

At block 712, the pin orientation determiner 408 compares on-boardaccelerometer data to pin accelerometer data. For example, the pinorientation determiner 408 can determine the difference between avehicle orientation based on the on-board accelerometer data to a pinorientation (e.g., the orientation determined based on the pitch data,etc.) Additionally or alternatively, the pin orientation determiner 408can compare the relative orientation to a vehicle orientation based onthe on-board accelerometer data.

At block 714, the hitch condition detector 410 determines if thecomparison of the on-board accelerometer data to pin accelerometer dataindicates a physical change in the hitch 108 has occurred. For example,the pin orientation determiner 408 can determine the difference betweenrelative orientation of the pins and the data received from the RCM ofthe vehicle 102 to determine if the difference satisfies a second faultthreshold (e.g., zero degrees, five degrees, etc.). If the comparison ofthe on-board accelerometer data to pin accelerometer data indicates aphysical fault in the hitch 108 has occurred (e.g., the second faultthreshold is satisfied, etc.), the method 700 advances to block 716. Ifthe comparison of the on-board accelerometer data to pin accelerometerdata does not indicate a physical fault in the hitch 108 has occurred(e.g., the second fault threshold is not satisfied, etc.), the method700 advances to block 718.

At block 716, the vehicle interface 412 reports the physical change hasoccurred in the hitch 108. For example, the vehicle interface 412 canreport a physical change to an ECU associate with the vehicle 102. Insome examples, the vehicle interface 412 can alert a user of the vehicle102 to indicate a physical change has occurred in the vehicle (e.g., viaa display, via dashboard light, via a sound alert, via an alert on theinstrument cluster, via an alert on the center console, via a mobiledevice associated with the user, etc.). After the execution of block716, the method 700 ends.

At block 718, the vehicle interface 412 accepts the measured hitchload(s) and/or payload. For example, the vehicle interface 412 cantransmit the measured hitch load(s) (e.g., the tongue load, the towedload, the lateral load, etc.) and/or payload to an ECU associated withthe vehicle 102. In some examples, the vehicle interface 412 can causethe measured hitch load and/or payload to be presented to a user of thevehicle 102. After the execution of block 718, the method 700 ends.

The method 800 of FIG. 8 begins at block 802. At block 802, the payloaddeterminer 406 determines if the pins detected a load change at the sametime as a pitch change. For example, the payload determiner 406 cancompare when a load change was detected by the change detector 404 towhen a pitch change was detected by the change detector 404 to determineif the time difference between the load change and the pitch changesatisfies a threshold (e.g., zero seconds, 2 seconds, etc.). In otherexamples, the payload determiner 406 can determine that a pitch changeand/or a load change has not occurred. If the payload determiner 406detected a load change at the same time as the pitch change (e.g., thedifference does satisfy the threshold, etc.) the method 800 advances toblock 806. If the payload determiner 406 did not detect a hitch loadchange at the same time as the load change (e.g., no load change wasdetected, the difference does not satisfy a threshold, etc.), the method800 advances to block 804.

At block 804, the payload determiner 406 calculates weight of a payloadusing vehicle properties. For example, the payload determiner 406 candetermine the weight of the payload 104 based on a vehicle configurationand/or a suspension property. In other examples, the payload determiner406 can determine the weight of the payload by any other suitable means.After the execution of block 804, the method 800 ends.

At block 806, the payload determiner 406 determines no payload has beenadded to the bed. For example, the payload determiner 406 can determinethat the detected pitch change was caused by the coupling of the trailer106 to the hitch 108.

The method 900 of FIG. 9 begins at block 902. At block 902, the pinorientation determiner 408 calculates the orientation (e.g., the firstaccelerometer orientation 608, etc.) of the first sensor pin 206 usinggravity vector 614. For example, the pin orientation determiner 408 canuse Equation (1) to calculate the orientation of the first sensor pin206 using the gravity vector 614. In some examples, the pin orientationdeterminer 408 can determine the orientation of the first sensor pin 206using an acceleration value measured by the first sensor pin 206. Inother examples, the pin orientation determiner 408 can determine theorientation of the first sensor pin 206 by any other suitable means.

At block 904, the pin orientation determiner 408 calculates theorientation of the second sensor pin 208 (e.g., the second accelerometerorientation 610, etc.) using the gravity vector 614. For example, thepin orientation determiner can use Equation (2) to calculate theorientation of the second sensor pin 208 using the gravity vector 614.In some examples, the pin orientation determiner 408 can determine theorientation of the second sensor pin 208 using an acceleration valuemeasured by the second sensor pin 208. In other examples, the pinorientation determiner 408 can determine the orientation of the secondsensor pin 208 by any other suitable means.

At block 906, the pin orientation determiner 408 determines the relativeorientation of the sensor pins 206, 208. For example, the pinorientation determiner 408 can determine the relative orientation of thesensor pins 206, 208 by comparing the orientation of the sensor pins206, 208. In other examples, the pin orientation determiner 408 candetermine the relative orientation of the sensor pins 206, 208 using anyother suitable means.

At block 908, the pin orientation determiner 408 compares the relativeorientation of the pins to the installation orientation of the sensorpins 206, 208. For example, the pin orientation determiner 408 cancompare the relative orientation of the sensor pins 206, 208 to theinstallation orientation of the sensor pins 206, 208. In some examples,the pin orientation determiner 408 further bases the comparison of therelative orientation of the sensor pins 206, 208 and the installationorientation of the sensor pins 206, 208 on a measurement of on-boardaccelerometer (e.g., from the RCM 110, etc.). In other examples, the pinorientation determiner 408 can compare the relative orientation by anyother suitable means. After the execution of block 908, the method 900ends.

FIG. 10 is a block diagram of an example processor platform 1000structured to execute the instructions of FIGS. 7-9 to implement theload manager 112 of FIGS. 1 and/or 3. The processor platform 1000 canbe, for example, a server, a personal computer, a workstation, aself-learning machine (e.g., a neural network), a mobile device (e.g., acell phone, a smart phone, a tablet such as an iPad™), a personaldigital assistant (PDA), an Internet appliance, a DVD player, a CDplayer, a digital video recorder, a Blu-ray player, a gaming console, apersonal video recorder, a set top box, a headset or other wearabledevice, or any other type of computing device.

The processor platform 1000 of the illustrated example includes aprocessor 1012. The processor 1012 of the illustrated example ishardware. For example, the processor 1012 can be implemented by one ormore integrated circuits, logic circuits, microprocessors, GPUs, DSPs,or controllers from any desired family or manufacturer. The hardwareprocessor may be a semiconductor based (e.g., silicon based) device. Inthis example, the processor implements the example sensor interface 402,the example change detector 404, the example payload determiner 406, theexample pin orientation determiner 408, the example hitch conditiondetector 410, and the example vehicle interface 412.

The processor 1012 of the illustrated example includes a local memory1013 (e.g., a cache). The processor 1012 of the illustrated example isin communication with a main memory including a volatile memory 1014 anda non-volatile memory 1016 via a bus 1018. The volatile memory 1014 maybe implemented by Synchronous Dynamic Random Access Memory (SDRAM),Dynamic Random Access Memory (DRAM), RAMBUS® Dynamic Random AccessMemory (RDRAM®) and/or any other type of random access memory device.The non-volatile memory 1016 may be implemented by flash memory and/orany other desired type of memory device. Access to the main memory 1014,1016 is controlled by a memory controller.

The processor platform 1000 of the illustrated example also includes aninterface circuit 1020. The interface circuit 1020 may be implemented byany type of interface standard, such as an Ethernet interface, auniversal serial bus (USB), a Bluetooth® interface, a near fieldcommunication (NFC) interface, and/or a PCI express interface.

In the illustrated example, one or more input devices 1022 are connectedto the interface circuit 1020. The input device(s) 1022 permit(s) a userto enter data and/or commands into the processor 1012. The inputdevice(s) can be implemented by, for example, an audio sensor, amicrophone, a camera (still or video), a keyboard, a button, a mouse, atouchscreen, a track-pad, a trackball, isopoint and/or a voicerecognition system.

One or more output devices 1024 are also connected to the interfacecircuit 1020 of the illustrated example. The output devices 1024 can beimplemented, for example, by display devices (e.g., a light emittingdiode (LED), an organic light emitting diode (OLED), a liquid crystaldisplay (LCD), a cathode ray tube display (CRT), an in-place switching(IPS) display, a touchscreen, etc.), a tactile output device, a printerand/or speaker. The interface circuit 1020 of the illustrated example,thus, typically includes a graphics driver card, a graphics driver chipand/or a graphics driver processor.

The interface circuit 1020 of the illustrated example also includes acommunication device such as a transmitter, a receiver, a transceiver, amodem, a residential gateway, a wireless access point, and/or a networkinterface to facilitate exchange of data with external machines (e.g.,computing devices of any kind) via a network 1026. The communication canbe via, for example, an Ethernet connection, a digital subscriber line(DSL) connection, a telephone line connection, a coaxial cable system, asatellite system, a line-of-site wireless system, a cellular telephonesystem, etc.

The processor platform 1000 of the illustrated example also includes oneor more mass storage devices 1028 for storing software and/or data.Examples of such mass storage devices 1028 include floppy disk drives,hard drive disks, compact disk drives, Blu-ray disk drives, redundantarray of independent disks (RAID) systems, and digital versatile disk(DVD) drives.

The machine executable instructions 1032 of FIGS. 7-9 may be stored inthe mass storage device 1028, in the volatile memory 1014, in thenon-volatile memory 1016, and/or on a removable non-transitory computerreadable storage medium such as a CD or DVD.

Example 1 includes an apparatus, comprising a pin orientation determinerto determine a first orientation of a first pin and a second orientationof a second pin, the first pin and the second pin disposed within ahitch, and calculate a relative orientation of the first pin and thesecond pin based on the first orientation and the second orientation,and a hitch condition detector to determine if a physical change hasoccurred in the hitch by comparing the relative orientation to aninstallation orientation of the first pin and the second pin.

Example 2 includes the apparatus of example 1, wherein the hitchcondition detector is further to determine if the physical change hasoccurred in the hitch by comparing the relative orientation to a vehicleorientation.

Example 3 includes the apparatus of example 2, wherein the vehicleorientation is calculated based an acceleration value generated by anaccelerometer of a vehicle coupled to the hitch.

Example 4 includes the apparatus of example 1, further including asensor interface to receive a first acceleration value and a secondacceleration value from a first accelerometer associated with the firstpin and a second accelerometer associated with the second pin,respectively, and the pin orientation determiner is further to calculatethe first orientation based on the first acceleration value and agravitational vector, and calculate the second orientation based on thesecond acceleration value and the gravitational vector.

Example 5 includes the apparatus of example 1, wherein the hitchincludes a crossbar, and the first pin and the second pin are atsubstantially the same vertical position relative to the crossbar.

Example 6 includes the apparatus of example 1, further including achange detector to detect, via the first pin and the second pin, a hitchload associated with a trailer coupled to the hitch, and a hitchcondition detector to accept the hitch load in response to determiningthe physical change has not occurred.

Example 7 includes the apparatus of example 1, wherein the pinorientation determiner determines if the physical change has occurred inthe hitch by comparing the relative orientation to an installationorientation of the first pin and the second pin by determining that thephysical change has occurred when a difference between the relativeorientation and the installation orientation satisfies a threshold.

Example 8 includes a method, comprising determining a first orientationof a first pin and a second orientation of a second pin, the first pinand the second pin disposed within a hitch, calculating a relativeorientation of the first pin and the second pin based on the firstorientation and the second orientation, and determining if a physicalchange has occurred in the hitch by comparing the relative orientationto an installation orientation of the first pin and the second pin.

Example 9 includes the method of example 8, further includingdetermining if the physical change has occurred in the hitch bycomparing the relative orientation to a vehicle orientation.

Example 10 includes the method of example 9, wherein the vehicleorientation is calculated based an acceleration value generated by anaccelerometer of a vehicle coupled to the hitch.

Example 11 includes the method of example 8, wherein the determining thefirst orientation of the first pin and the second orientation of asecond pin includes receiving a first acceleration value and a secondacceleration value from a first accelerometer associated with the firstpin and a second accelerometer associated with the second pin,respectively, calculating the first orientation based on the firstacceleration value and a gravitational vector, and calculating thesecond orientation based on the second acceleration value and thegravitational vector.

Example 12 includes the method of example 8, wherein the hitch includesa crossbar, and the first pin and the second pin are at substantiallythe same vertical position relative to the crossbar.

Example 13 includes the method of example 8, further includingdetecting, via the first pin and the second pin, a hitch load associatedwith a trailer coupled to the hitch and accepting the hitch load inresponse to determining the physical change has not occurred.

Example 14 includes the method of example 8, wherein the determining ifthe physical change has occurred in the hitch by comparing the relativeorientation to an installation orientation of the first pin and thesecond pin includes determining that the physical change has occurredwhen a difference between the relative orientation and the installationorientation satisfies a threshold.

Example 15 includes a non-transitory machine-readable storage mediumincluding instructions which, when executed, cause a processor to atleast determine a first orientation of a first pin and a secondorientation of a second pin, the first pin and the second pin disposedwithin a hitch, calculate a relative orientation of the first pin andthe second pin based on the first orientation and the secondorientation, and determine if a physical change has occurred in thehitch by comparing the relative orientation to an installationorientation of the first pin and the second pin.

Example 16 includes the non-transitory machine-readable storage mediumof example 15, wherein the instructions, when executed, further causethe processor to determine if the physical change has occurred in thehitch by comparing the relative orientation to a vehicle orientation.

Example 17 includes the non-transitory machine-readable storage mediumof example 16, wherein the vehicle orientation is calculated based anacceleration value generated by an accelerometer of a vehicle coupled tothe hitch.

Example 18 includes the non-transitory machine-readable storage mediumof example 15, wherein the instructions, when executed, further causethe processor to receive a first acceleration value and a secondacceleration value from a first accelerometer associated with the firstpin and a second accelerometer associated with the second pin,respectively, calculate the first orientation based on the firstacceleration value and a gravitational vector, and calculate the secondorientation based on the second acceleration value and the gravitationalvector.

Example 19 includes the non-transitory machine-readable storage mediumof example 15, wherein the instructions, when executed, further causethe processor to detect, via the first pin and the second pin, a hitchload associated with a trailer coupled to the hitch, and accept thehitch load in response to determining the physical change has notoccurred.

Example 20 includes the non-transitory machine-readable storage mediumof example 15, wherein the determining if the physical change hasoccurred in the hitch by comparing the relative orientation to aninstallation orientation of the first pin and the second pin includesdetermining that the physical change has occurred when a differencebetween the relative orientation and the installation orientationsatisfies a threshold.

Example 21 includes an apparatus, comprising a hitch change detector todetect, via an accelerometer of a hitch, a pitch angle change of avehicle, and a payload determiner to determine if a hitch load changeoccurred within a threshold time after the pitch angle change, and inresponse to determining the hitch load change occurred within thethreshold time, calculate a weight associated with a payload within abed of the vehicle based on a property of the vehicle.

Example 22 includes the apparatus of example 21, wherein the payloaddeterminer is further to, in response to determining the hitch loadchange did not occur within the threshold time, determine no payload hasbeen disposed within the bed of the vehicle.

Example 23 includes the apparatus of example 21, wherein the property ofthe vehicle includes at least one of a vehicle configuration or asuspension property.

Example 24 includes the apparatus of example 21, wherein theaccelerometer is within a pin of the hitch.

Example 25 includes the apparatus of example 21, wherein the hitch loadchange is associated with a coupling of a trailer to the vehicle via thehitch.

Example 26 includes the apparatus of example 25, wherein the pitch anglechange is associated with at least one of the coupling of the trailer tothe vehicle or an addition of the payload to the vehicle.

Example 27 includes the apparatus of example 21, wherein the payloaddeterminer calculates the weight associated with the payload disposedwithin the bed of the vehicle without input from a sensor associatedwith a suspension system of the vehicle.

Example 28 includes a method, comprising detecting, via an accelerometerof a hitch, a pitch angle change of a vehicle, determining if a hitchload change occurred within a threshold time after the pitch anglechange, and in response to determining the hitch load change occurredwithin the threshold time, calculating a weight associated with apayload within a bed of the vehicle based on a property of the vehicle.

Example 29 includes the method of example 28, further including inresponse to determining the hitch load change did not occur within thethreshold time, determining no payload has been disposed within the bedof the vehicle.

Example 30 includes the method of example 28, wherein the property ofthe vehicle includes at least one of a vehicle configuration or asuspension property.

Example 31 includes the method of example 28, wherein the accelerometeris within a pin of the hitch.

Example 32 includes the method of example 28, wherein the hitch loadchange is associated with a coupling of a trailer to the vehicle via thehitch.

Example 33 includes the method of example 32, wherein the pitch anglechange is associated with at least one of the coupling of the trailer tothe vehicle or an addition of the payload to the vehicle.

Example 34 includes the method of example 28, wherein the calculatingthe weight associated with the payload disposed within the bed of thevehicle is performed without input from a sensor associated with asuspension system of the vehicle.

Example 35 includes a non-transitory machine-readable storage mediumincluding instructions which, when executed, cause a processor to atleast detect, via an accelerometer of a hitch, a pitch angle change of avehicle, determine if a hitch load change occurred within a thresholdtime after the pitch angle change, and in response to determining thehitch load change occurred within the threshold time, calculate a weightassociated with a payload within a bed of the vehicle based on aproperty of the vehicle.

Example 36 includes the non-transitory machine-readable storage mediumof example 35, wherein the instructions further cause the processor to,in response to determining the hitch load change did not occur withinthe threshold time, determine no payload has been disposed within thebed of the vehicle.

Example 37 includes the non-transitory machine-readable storage mediumof example 35, wherein the property of the vehicle includes at least oneof a vehicle configuration or a suspension property.

Example 38 includes the non-transitory machine-readable storage mediumof example 35, wherein the hitch load change is associated with acoupling of a trailer to the vehicle via the hitch.

Example 39 includes the non-transitory machine-readable storage mediumof example 38, wherein the pitch angle change is associated with atleast one of the coupling of the trailer to the vehicle or an additionof the payload to the vehicle.

Example 40 includes the non-transitory machine-readable storage mediumof example 35, wherein the processor calculates the weight associatedwith the payload disposed within the bed of the vehicle is performedwithout input from a sensor associated with a suspension system of thevehicle.

Although certain example methods, apparatus and articles of manufacturehave been disclosed herein, the scope of coverage of this patent is notlimited thereto. On the contrary, this patent covers all methods,apparatus and articles of manufacture fairly falling within the scope ofthe claims of this patent.

1. An apparatus, comprising: a pin orientation determiner to: determinea first orientation of a first pin and a second orientation of a secondpin, the first pin and the second pin disposed within a hitch; andcalculate a relative orientation of the first pin and the second pinbased on the first orientation and the second orientation; and a hitchcondition detector to determine if a physical change has occurred in thehitch by comparing the relative orientation to an installationorientation of the first pin and the second pin.
 2. The apparatus ofclaim 1, wherein the hitch condition detector is further to determine ifthe physical change has occurred in the hitch by comparing the relativeorientation to a vehicle orientation.
 3. The apparatus of claim 2,wherein the vehicle orientation is calculated based an accelerationvalue generated by an accelerometer of a vehicle coupled to the hitch.4. The apparatus of claim 1, further including: a sensor interface toreceive a first acceleration value and a second acceleration value froma first accelerometer associated with the first pin and a secondaccelerometer associated with the second pin, respectively; and the pinorientation determiner is further to: calculate the first orientationbased on the first acceleration value and a gravitational vector; andcalculate the second orientation based on the second acceleration valueand the gravitational vector.
 5. The apparatus of claim 1, wherein thehitch includes a crossbar, and the first pin and the second pin are atsubstantially the same vertical position relative to the crossbar. 6.The apparatus of claim 1, further including: a change detector todetect, via the first pin and the second pin, a hitch load associatedwith a trailer coupled to the hitch; and a hitch condition detector toaccept the hitch load in response to determining the physical change hasnot occurred.
 7. The apparatus of claim 1, wherein the pin orientationdeterminer determines if the physical change has occurred in the hitchby comparing the relative orientation to an installation orientation ofthe first pin and the second pin by determining that the physical changehas occurred when a difference between the relative orientation and theinstallation orientation satisfies a threshold.
 8. A method, comprising:determining a first orientation of a first pin and a second orientationof a second pin, the first pin and the second pin disposed within ahitch; calculating a relative orientation of the first pin and thesecond pin based on the first orientation and the second orientation;and determining if a physical change has occurred in the hitch bycomparing the relative orientation to an installation orientation of thefirst pin and the second pin.
 9. The method of claim 8, furtherincluding determining if the physical change has occurred in the hitchby comparing the relative orientation to a vehicle orientation.
 10. Themethod of claim 9, wherein the vehicle orientation is calculated basedan acceleration value generated by an accelerometer of a vehicle coupledto the hitch.
 11. The method of claim 8, wherein the determining thefirst orientation of the first pin and the second orientation of asecond pin includes: receiving a first acceleration value and a secondacceleration value from a first accelerometer associated with the firstpin and a second accelerometer associated with the second pin,respectively; calculating the first orientation based on the firstacceleration value and a gravitational vector; and calculating thesecond orientation based on the second acceleration value and thegravitational vector.
 12. The method of claim 8, wherein the hitchincludes a crossbar, and the first pin and the second pin are atsubstantially the same vertical position relative to the crossbar. 13.The method of claim 8, further including: detecting, via the first pinand the second pin, a hitch load associated with a trailer coupled tothe hitch; and accepting the hitch load in response to determining thephysical change has not occurred.
 14. The method of claim 8, wherein thedetermining if the physical change has occurred in the hitch bycomparing the relative orientation to an installation orientation of thefirst pin and the second pin includes determining that the physicalchange has occurred when a difference between the relative orientationand the installation orientation satisfies a threshold.
 15. Anon-transitory machine-readable storage medium including instructionswhich, when executed, cause a processor to at least: determine a firstorientation of a first pin and a second orientation of a second pin, thefirst pin and the second pin disposed within a hitch; calculate arelative orientation of the first pin and the second pin based on thefirst orientation and the second orientation; and determine if aphysical change has occurred in the hitch by comparing the relativeorientation to an installation orientation of the first pin and thesecond pin.
 16. The non-transitory machine-readable storage medium ofclaim 15, wherein the instructions, when executed, further cause theprocessor to determine if the physical change has occurred in the hitchby comparing the relative orientation to a vehicle orientation.
 17. Thenon-transitory machine-readable storage medium of claim 16, wherein thevehicle orientation is calculated based an acceleration value generatedby an accelerometer of a vehicle coupled to the hitch.
 18. Thenon-transitory machine-readable storage medium of claim 15, wherein theinstructions, when executed, further cause the processor to: receive afirst acceleration value and a second acceleration value from a firstaccelerometer associated with the first pin and a second accelerometerassociated with the second pin, respectively; calculate the firstorientation based on the first acceleration value and a gravitationalvector; and calculate the second orientation based on the secondacceleration value and the gravitational vector.
 19. The non-transitorymachine-readable storage medium of claim 15, wherein the instructions,when executed, further cause the processor to: detect, via the first pinand the second pin, a hitch load associated with a trailer coupled tothe hitch; and accept the hitch load in response to determining thephysical change has not occurred.
 20. The non-transitorymachine-readable storage medium of claim 15, wherein the determining ifthe physical change has occurred in the hitch by comparing the relativeorientation to an installation orientation of the first pin and thesecond pin includes determining that the physical change has occurredwhen a difference between the relative orientation and the installationorientation satisfies a threshold.
 21. (canceled)
 22. (canceled) 23.(canceled)
 24. (canceled)
 25. (canceled)
 26. (canceled)
 27. (canceled)28. (canceled)
 29. (canceled)
 30. (canceled)
 31. (canceled) 32.(canceled)
 33. (canceled)
 34. (canceled)
 35. (canceled)
 36. (canceled)37. (canceled)
 38. (canceled)
 39. (canceled)
 40. (canceled)